Select Strategies for Reservoir Blue Catfish
June 03, 2014
One of Jerry Martin's favorite central Texas lakes is 56-year-old Lake Whitney. The water in the lower two-thirds of its 23,560 acres is clear. It contains a variety of aquatic vegetation and submerged timber, as well as limestone bluffs, rocky points, gravel flats and mudflats. Its maximum depth plummets to 108 feet near the dam and is almost 100 feet deep seven miles upstream.
Blue catfish were stocked about 20 years ago. Since then they have reproduced bountifully, and Martin often tangles with more than a 100 on each outing. The average size ranges from 15 to 18 inches, but he occasionally catches 5- to 10-pounders. His biggest weighed 45 pounds.
In the dead of winter, he finds vast numbers of blue cats tightly schooled in 90 feet of water in the lower portions of the lake. Then in late February, as fewer cold fronts pummel central Texas and warm rains fall, blues sashay into shallower environs, following shad out of Whitney's deepest confines.
By nature shad are nomadic, and they're thought to be the first species in a reservoir to respond to changing conditions. Shad, therefore, move before blue cats do. Because shad are the blue cats' primary prey, they often dictate the larger fishes' whereabouts. White bass also eat shad, and when schools of white bass are seen feeding on shad, blue catfish likely are nearby.
When the water temperature hovers in the low-50°F range in March, most blues hold in 50 feet of water, with a few at 90 feet and some shallower than 50. As the water warms, the large wintertime schools disintegrate, individuals and small pods scattering about the reservoir and moving shallower to follow shad.
In deep-water situations, Martin uses sonar to monitor the movement of gizzard and threadfin shad and to see how blue catfish respond to their movements. When the blues occupy shallow areas, he looks for shad dimpling the surface or cruising slightly under the surface.
At Lake Whitney blues can be scattered, but the bulk of them abide in two primary locales and depths in the spring and summer — one shallow and one deep.
By the time the water temperature reaches 60°F in late March, he finds concentrations of blues and shad in 20 to 30 feet of water on mudflats, with another large group milling about in 3 to 10 feet of water on the same flats. Sometimes the shallow and deep cats are only 70 feet apart, so Martin anchors his boat between the two groups and catches fish from each.
Biologists in Oklahoma have noted that blue catfish prefer to suspend rather than move about on the bottom. When they're in deep-water locales in spring and summer, Martin often finds them suspended 10 feet below the surface and 20 feet above bottom — at times, they suspend as shallow as 3 feet under the surface.
Another suspending situation can occur after a heavy rainstorm. Several years ago in early May a massive thunderstorm hit central Texas, and in the rising water, Martin spotted blue cats foraging on shad near Lake Whitney's surface at the mouth of a feeder creek, which was about 250 yards wide and 10 feet deep.
Like shad, blues also commence spawning in mid-May and continue until mid-June. Some blue catfish anglers in the Heartland say that fishing for blue cats during the spawn is problematic, but at Whitney the spawn doesn't have an adverse effect on fishing. He often catches the biggest blues of the year in early June, when he finds them on flats littered with wisps of brush or stick-ups.
Because not all blues spawn simultaneously, shad behavior and location can still be critical during the spawning season. In any case, the key to finding numbers of blue catfish is pinpointing large concentrations of shad.
Lake Whitney contains both gravel and mudflats. Mud is the most fruitful area to fish. The exception occurs when blues feed on shad spawning on gravel flats, from mid-May to mid-June.
After spawning, blue cats return to their wandering ways in their pursuit of shad. During the mornings in late June, blues cruise mudflats, often favoring wind-blown areas, in 21â„2 to 10 feet of water; sometimes they remain active at those spots and depths all day long.
But by mid-July, which is brutally hot in central Texas, the morning activity gradually diminishes as the sun climbs higher and burns hotter, and the feeding activity ceases before noon. Then about sundown it resumes as the blues chase shad in 3 to 6 feet of water on the mudflats.
A thermocline accompanies the hot weather and limits the vertical movements of the shad to no deeper than 25 feet. Martin occasionally catches blues below the thermocline, but nowadays he doesn't fish deeper than 25 feet during the heat of the summer, he says.
In addition to his shallow-water pattern on mudflats, he plies points and humps in summer, focusing on wind-blown spots. He anchors in 10 feet of water and places his baits in 6, 12, and 23 feet of water.
In central Texas, summer weather stretches into October. Martin says that the best times to find actively feeding blues occurs during the morning and evening hours, from mid-July till early October.
Grand Lake and Lake of the Ozarks
Jeff Williams has spent countless days examining the ways of blue catfish in Lake of the Ozarks, Missouri, and Grand Lake, Oklahoma. He finds similarities both between the lakes and their denizens. Both lakes are old, massive, and cluttered with homes, docks, and recreational boaters. Lake of the Ozarks, for instance, is 75 years old, 93 miles long, and covers 54,000 acres; Grand Lake is 65 years old and 59,200 acres. Both lakes contain significant populations of 18- to 24-inch blue catfish.
Unlike Martin, Williams targets only blues weighing more than 20 pounds. There aren't a lot of Goliath-sized blues abiding in Grand — a 47-pounder is his biggest. He suspects that some 100-pounders lurk in Lake of the Ozarks; his biggest there weighed 61 pounds.
At Lake of the Ozarks, Williams fishes mile 35 to mile 93, and he works a similar segment of Grand Lake stretching from Miami, Oklahoma, to the mouth of Horse Creek. The bottom composition of both reservoirs is silt in the upper ends and rock in the lower portions. Grand Lake, however, is shallower.
In the blue cat's world, spring commences at both lakes in mid-March, when the water temperature reaches 50°F. At this time, some actively feeding blues are in water deeper than 30 feet, and another contingent is in 6 to 10 feet at the end of massive mudflats that extend 100 yards into the lake.
As water warms and the spawn approaches, more and more blues move into shallow environs, and ultimately most of the deep-water lairs become barren. By April and May, blue cats mill about on mudflats in 3 to 8 feet of water, foraging on shad.
From his experiences at both reservoirs, he says that small and medium-sized blue catfish follow schools of shad, but big blues don't. The big ones are mavericks and loners, and anglers should fish for them with precision and patience, targeting specific big catfish coverts.
Blues prefer to consume dead shad during cold-fronts in the spring, but after the weather turns balmy and the wind angles out of the south for several days, they display a fondness for live shad.
Throughout June until early July, the blues' fancy turns from eating shad to spawning, and Williams hasn't found a way to consistently catch trophy-sized blue cats during the spawn at Lake of the Ozarks.
At Grand Lake, however, he's been able to catch them at night by traveling in a jet boat up the Spring and Neosho rivers, where they're in extremely shallow water that's buffeted by a current flow of 2,000 to 5,000 cubic feet per second (cfs). By early July, blues leave those rivers and return to the Grand's main body.
After the spawn until about October, most of the blues are on mudflats in 15 to 25 feet of water, as well as on or around humps that are shallower than the thermocline, which normally lies at 25 feet. However, at Lake of the Ozarks during the summer of 2004, Williams seldom found a significant thermocline. He suspects that the vast volume of water that flowed out of Truman Dam through the lake to Bagnell Dam prevented a thermocline.
One of his favorite midlake humps at Lake of the Ozarks crests at 23 feet. It's surrounded by the Osage River channel, and the edge of the channel and mudflat is in 18 feet of water.
At Grand Lake, one of his treasured humps sits at the mouth of a big cove, with its top reaching a depth of 40 feet. The submerged Neosho River channel, 75 feet deep, courses within 20 feet of the hump's outside edge, and its other sides are surrounded by 55 feet of water. Around this hump, he regularly catches blues suspended in 38 feet of water, 13 feet deeper than the thermocline. He suspects that the cats are either under the thermocline, or that some feature like current causes the thermocline to dissipate at this hump.
Even though he catches big blues suspended around this hump, he normally finds that suspended trophy-sized blues are difficult to entice — especially the ones hovering around the thermocline. He says jug-liners regularly catch big blues, but notes they accomplish this by overwhelming the fish with a lot more baited hooks than he can present.
Williams believes most of the trophy-sized blue catfish at Grand and Lake of the Ozarks feed on the bottom, so he mostly fishes on bottom.
Tailrace Tactics: A unique feature at Lake of the Ozarks is the tailrace below Truman Dam. Steve Brown spends many nights and days plying this segment of the lake, which stretches from mile 74 to mile 93.
On an average outing, he and his guide parties tangle with about 18 blue catfish and a couple of them might weigh 20 pounds. On a fantastic outing, they typically catch more than 60 blues. The biggest they've landed weighed 72 pounds.
Brown says current is a critical element on this 21-mile portion of the lake, since irregular flows mean paltry fishing. If the current ceases for a long spell, fishing for blue cats can be fruitful — this is part of the regularity equation. But if the current flow is erratic, the fishing is usually horrible.
Another significant factor is the number of turbines that jettison current from the dam into the tailrace. One turbine is meaningless, but two can create some fine fishing. If the current flow has been nil for a week, and then two begin to steadily flow, fishing improves immediately. If two turbines continue to flow uninterruptedly, and a third one commences to run, the fishing can be spectacular. When that occurs, he can anchor and fish any covert from Warsaw to Deer Creek.
When the flow exceeds three turbines and water gushes out of the floodgates, however, the parameters change. Now Brown plies current breaks at the mouth of a creek or along some prominent bends in the river channel, where baitfish and blue catfish gather to seek shelter from the powerful current.
He typically fishes the upper 21 miles of the lake from March until the second week in July. By mid-July, the current flow often becomes erratic, which adversely affects the fishing. May is the best month, with June the most problematic because of the spawn.
But if the water flow is voluminous and consistent, fishing can be rewarding during the late stages of the spawn. On one late June day, conditions unfolded perfectly for Brown and Williams, who were enjoying a busman's holiday together. Some blues had begun spawning earlier than normal, so that some had finished their reproductive rituals sooner. Moreover, a large, steady flow of water had rolled out of the dam for several weeks.
Around sundown, as 34,700 cfs coursed down the tailrace, Brown and Williams anchored several miles east of Warsaw on a stairstep ledge that sheltered blues and shad from the heavy current. By midnight, they'd caught and released a belligerent 56-pound blue and tangled with 10 smaller ones.
To further illustrate the profound effect that the tailrace can have on blue catfish in the Lake of the Ozarks, Brown visited the observation area at Truman Dam on a late June day. He peered down at 24,700 cfs of water boiling into the lake and watched countless blue cats — some of them huge — roiling on the surface next to the dam. It proved again the bewitching influence tailrace current has on some blue catfish — even after the spawn, when wisdom has it that they migrate down-lake.
In July and August, the grasshopper phenomenon erupts, and as the hot Texas wind blows grasshoppers onto Lake Whitney's surface, Martin often finds massive pods of hoppers as far as 100 feet from the shoreline. The grasshopper invasion provokes the channel catfish and some blue cats to slurp grasshoppers off the surface.